[clang] [llvm] [WebAssembly] Implement prototype f32.store_f16 instruction. (PR #91545)

[Derek Schuff via cfe-commits]

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@@ -192,6 +192,7 @@ TARGET_BUILTIN(__builtin_wasm_relaxed_dot_bf16x8_add_f32_f32x4, "V4fV8UsV8UsV4f"
 
 // Half-Precision (fp16)
 TARGET_BUILTIN(__builtin_wasm_loadf16_f32, "fh*", "nU", "half-precision")
+TARGET_BUILTIN(__builtin_wasm_storef16_f32, "vfh*", "nU", "half-precision")
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dschuff wrote:

The only documentation I know of for this is https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html
Clang has https://clang.llvm.org/docs/AttributeReference.html but it's not helpful here.

I guess a store shouldn't be pure, since it has an observable side effect, and in any case it doesn't return a value.

https://github.com/llvm/llvm-project/pull/91545